Hi Nicola,
you wrote:
>The reason why locations are not parts of objects is due to the very
>nature of objects and locations, not to the specificity of the part
>relation. The part relation is general, various entities behave very
>differently with respect to it, that's why there are various kinds of
>entities, but just one kind of (general) part...
(G.V.)
>>Are we sure that, when we say <'hour' part of 'day'> and
>><'wheel' part of 'car'> we are using the same 'part' relation ?
>Yes.
I have a deep interest in the metaphysical assumption I see behind your
opinion (monism). Of course, it is as a specific position among many
others. For sure, monism is not the metaphysics position closest to the
'common sense'. Many authors (e.g. Achille Varzi, "Parole, Oggetti,
Eventi", 2001 ) recognize that natural language does not witness in favour
of the reduction of all entities to time-spatial events. In fact, objects
and events are reflected into different syntactic categories. Now, I think
that we should be as close to the common sense as possible, "salva
veritatem".
> ...there is no need to introduce a relation
>as primitive if it can be axiomatized. However, you need a suitable
>expressivity for axiomatizing it (for instance, to express the
>supplementation axiom).
On this, I see that there is a general agreement. Personally, I think that
the language should allow a sort of 'rigid denotation' for 'standard
axioms' such as those realated to mereology. I mean: the possibility to
refer them with simple identifiers rather than full specified logic
expressions. Most of the semantic web application wouldn't be able to
evaluate arbitrary logic expressions anyway.
(G.V.)
>>Finally, I insist on the need of introducing 'type' vs. 'role' as
modifiers
>>for class declarations. This distinction (that I learned from your works)
>>woud be crucial for for many practical reasons. Have you any comment on
>>that ?
>Of course we need these things. Type vs. role is certainly a very
>important distinction for an ontology language.
Fine. We should work on this in the future. Is there room for a proposal in
this direction ?
Regards,
Guido Vetere